hbase行键过滤器RowFilter

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RowFilter是用来对rowkey进行过滤的,比较符如下:

Operator

Description

LESS

小于

LESS_OR_EQUAL

小于等于

EQUAL

等于

NOT_EQUAL

不等于

GREATER_OR_EQUAL

大于等于

GREATER

大于

NO_OP

排除所有

Comparator

Description

BinaryComparator

使用Bytes.compareTo()比较

BinaryPrefixComparator

和BinaryComparator差不多，从前面开始比较

NullComparator

Does not compare against an actual value but whether a given one is null, or not null.

BitComparator

Performs a bitwise comparison, providing a BitwiseOp class with AND, OR, and XOR operators.

RegexStringComparator

正则表达式

SubstringComparator

把数据当成字符串，用contains()来判断

下面是相关比较符的例子

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package com.hxl;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.BinaryComparator;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.RowFilter;
import org.apache.hadoop.hbase.util.Bytes;
import com.hxl.ConnectDB;
public class RowFilterTest {
publicvoid rowfilter(String tablename,String rowkeyvalue){
Configurationconfiguration = null;
configuration= new ConnectDB().getConf();
try{
HTable table= new HTable(configuration, tablename);
Filter filter1= new RowFilter(CompareFilter.CompareOp.EQUAL,
new BinaryComparator(Bytes.toBytes(rowkeyvalue)));
// EQUAL =
Scan s =new Scan();
s.setFilter(filter1);
ResultScanner rs =table.getScanner(s);
for(Result r: rs){
System.out.println("rowkey:"+ new String(r.getRow()));
for(KeyValue keyValue: r.raw()){
System.out.println("列族:"+ new String(keyValue.getFamily())
+" 列:" + new String(keyValue.getQualifier())+ ":"
+new String(keyValue.getValue()));
}
}
}catch (IOException e){
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

相关的过滤方法使用:
提取rowkey以01结尾数据
Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new RegexStringComparator(".*01$"));

提取rowkey以包含201407的数据
Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new SubstringComparator("201407"));

提取rowkey以123开头的数据
Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new BinaryPrefixComparator("123".getBytes()));

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